This proposal describes the theory, design, and investigations with a no-touch ocular pulse measurement (NTOPM) instrument which uses continuous-wave ultrasound reflected from the cornea in air to record minute corneal displacements caused by blood pressure pulsations in the globe. There is no physical contact with the eyes and very little ultrasonic energy is absorbed by them, hence use of the instrument involves negligible risk. A phase-lock technique is used to measure the corneal displacement to within plus or minus 1 micron m. Transducers will be mounted on adjustable optometrist's trial frames. The NTOPM system is intended to be used in the diagnosis of carotid occlusions which often lead to stroke. We hope to demonstrate its effectiveness in such diagnoses. Rabbits and human subjects will be used. The possibility that the system can also be used to detect glaucoma will also be investigated. We envision the fully-developed instrument as having application in screening asymptomatic outpatients in health maintenance programs. It promises to be relatively inexpensive and quick and easy to use. Patients detected as having carotid occlusion would be referred to established diagnostic procedures for carotid insufficiency. A prototype of the NTOPM instrument has been built and tested. It is on the satisfactory performance of this system that this proposal is based.